The last time I tried to switch over from my personal SSN to Corp, BN told me that I had to Close my current BN account and reopen another in my business name. Once a personal account is created, it cannot be updated later to a business account which I thought was totally stupid because you can update your information at Smashwords and Amazon with no problems. So, I gave up and left it as it is. I don't want to go through the trouble of making that kind of change as I have over 20 books published, and I have no idea what that would do to my sales rank and the reviews I already have for many of my books.

Here's the link they gave me when they sent me the reply to an email I sent them (of course, it took them ages to reply to it).

Unfortunately, at this time the system does not allow for the taxinformation to be updated after an account has been accepted. Please beadvised that this will not affect your payments from being processed.

If you would like to open a publishing account under your business you may do so by terminating your current account and opening a new account under your company name.